1. Field of the invention
The present invention relates to the devices for suspending or hanging resilient bands or straps out of a possibly translucent plastic material or the like, which are widely utilized for closing doors of industrial premises or for partitioning, insulating or hiding quarters inside or outside a building by a curtain or screen made of several depending straps.
2. Description of the prior art
In such a kind of closure means, the straps are usually suspended by the upper end and overlap laterally at least partially so as to form a resilient distortable restorable curtain which is easily traversable by persons, vehicles or loads while insuring a convenient sealing to the draughts and the thermal losses. Generally, the straps are each rigidly suspended by means of a hanging device comprised by two assembled shells in gripping engagement on one hand with the upper end of the resilient strap and on the other hand with a hanging metal section having the shape or .
When superstructures of vehicles or loads traversing the screen pass adjacent the hanging device, said latter cannot follow the displacement of the straps which accordingly are submitted at the upper portion thereof to heavy bending stresses causing rapidly the straps to be worn or torn.
In order to obviate such drawbacks, it has been proposed to suspend the resilient straps out of plastic material by means of a hanging device comprised by two shells which are rigidly connected at the lower part thereof to the upper part of the strap and which are pivotally mounted at the upper part thereof around a rectilinear rod or tube serving as a stready hanging device extending longitudinally in the plane of the door under the ceiling or under a lintal. When a load traverses the strap curtain and passes very close to the strap hanging devices, the shells to which the straps are secured may be deflected angularly without causing locally injuring bending of the straps. Practically, the pivoting mounting of the shells on the tube or the rod is a direct mounting "iron/iron" without a specific machining of the parts and without utilization of bearings or bushings even if the different elements have been previously subject to a corrosion-proof treatment such as electroplating or galvanizing. By reason of the wear, the protective treatment progressively disappears and in corrosive or moist atmosphere, more particularly if the curtain is installed outside a building, stain appear quickly and progressively hinders the pivoting movement of the shells. On the other hand, in order to allow convenient pivoting displacement of the shells on the suspension tube or rod, said tube cannot be mounted directly onto the lintal or the ceiling and has to be set slightly apart therefrom whereby leaving a space between the tube and the ceiling or the lintal in an arrangement which is detrimental to a convenient air-sealing by the curtain.
In order to partially obviate such drawbacks, it has been further proposed a strap hanging device comprising, on one hand, a hanging hollow U-shaped beam provided with oscillating apertures extending transversally to its longitudinal axis and, on the other hand, hanging members the lower portion of which is secured rigidly to the upper portion of a resilient strap out of plastic material and the upper portion of which has a substantially T-shaped outwardly extending small hook. Said T-shaped small hooks at the upper portion of the hanging members are engaged within the wider parts of the oscillating apertures formed in the U-shaped beam so as to come to a freely bearing position on the bottom of the beam where the width of the apertures is reduced.
A drawback of such a system resides in the poor sealing at the upper part of the resilient curtain resulting, on one hand, from the apertures formed in the U-shaped beam and separated one from each other from a distance of about 5 to 10 cm, and, on the other hand, from the clearing distance between the upper part of the strap hanging members forming the small T-shaped suspending hooks and the bottom portion of the U-shaped beam.
Another drawback resides in the fact that the apertures formed in the U-shaped beam reduce the mechanical strength of the beam with accordingly the requirement of necessarily increasing the number of mounting means for securing the beam to the ceiling or the lintal.
It has also been proposed hanging devices including a two-part hanging beam consisting of a C-shaped part and a cover part. The horizontally extending upper flange or the vertically extending web of the C-shaped part serves to mount the assembly to the lintal or ceiling when the lower flange of the C-shaped part is is formed with parallel slots in a comb-like configuration for hooking the strap hanging members formed with hooking holes. The second part serves as a cover for the C-shaped part and is mounted thereon when the strap hanging members have been installed on the comb-like lower flange of the C-shaped part to prevent a withdrawal of said hanging members when the straps are displaced or spread as the result of passages of vehicles, persons or loads through the strap curtain.
However, with such an arrangement, when a load traverses the strap curtain, the forces exerted by the displaced, e.g. pushed straps onto the hanging members may cause same to unfasten the cover part which is usually simply spring engaged therewith.